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Kittens’ Eyes Sewn Shut to Research Treatment for Humans

Kittens’ Eyes Sewn Shut to Research Treatment for Humans

A new study of seven kittens suggests a new treatment for amblyopia or “lazy eye” in humans. The kittens did not themselves have the disorder (in which one eye works but the connections between it and the brain are disrupted). It was induced via a procedure called monocular deprivation, in which one of the eyelids of each kitten was sewn shut 30 days after birth, a critical period for the development of vision.

The kittens all, thankfully, regained their vision. That is, the proposed treatment for amyblopia — placing them in total darkness for ten days straight — was successful. While monocular deprivation “does no lasting harm to the kittens’ eyes or eyelids” according to NPR, the kittens did have to undergo painful procedures that are simply not be thinkable to carry out on humans.

In the experiment, a week after the surgery, the kittens’ eyes were reopened and they were found to be unable to see out of one eye. They were placed in total darkness, some right after having their eyes re-opened and others for five to eight weeks. The kittens who were immediately placed in the darkness regained their vision after seven weeks. But the others, whose “treatment” was delayed, regained their vision after five to seven days.

The Dalhousie University scientists who conducted the experiment attribute the kittens being able to get their eyesight back to their brains’ visual system being in an early stage of development. Young kittens have low levels of a protein called neurofilaments while older cats have more. Neurofilaments are described as”rigid scaffolding” in the brain and are thought to reduce its plasticity. Young kittens’ brains are therefore more able to adapt and change than those of adults.

Amblyopia in human children is now usually treated by placing a patch over the dominant eye, to make the “lazy eye” get stronger. There are side effects, such as the loss of depth perception and a weakening of the dominant eye. (Anecdotally, my late mother-in-law, sister-in-law and niece all had a lazy eye and wore a patch, with no lasting side effects.)

As NPR observes a bit tongue-in-cheekily, scientists emphasize that immersion-in-darkness as a potential treatment for lazy eye in humans is not even being considered and that “we shouldn’t start throwing children into the dark just yet.” The logistics — having a child stay in total darkness for a period of days — would certainly be complicated.

While it is a huge relief to know that the kittens in the experiment all regained their eyesight, it is an understatement to say that the study raises huge ethical questions. There is a need to study the brain and how it functions to develop new treatments. But knowing that kittens were deliberately blinded and placed in the dark for days to make new discoveries casts a shadow over the study and its findings.

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12:52AM PDT on Jun 8, 2013

I had surgery when I was 13 to correct this particular condition in both eyes. In no way do I believe that what these people are doing in the name of "science" is right, ethical, or to the benefit of people like me who have this particular condition. Lazy eye is not fun, however it is easily corrected through either surgery or extensive exercises with the eyes. There is no need to torture and mutilate animals. I am utterly appalled and heartbroken, the sad thing is that I am no longer surprised. This isn't science, this is playing God and pretending it is science. True science should benefit all and it should hurt no one, human or animal. I have made a concerted effort my whole life, and I have a lot of health problems, to make sure that all of the medications I am forced to use are humane. I would appreciate it if more researchers realized that there is a growing number of individuals such as myself who are taking this stance. I would also like to add that as a scientist you can not say "animals are unlike human so we can test on them yet they feel emotional, psychological, and physical pain so we can test on them." Whenever I hear researchers or scientist say that I am dumbfounded. Obviously animals are like humans in that they have rich emotional and psychological lives, feel pain, suffer, and need the protection of others. That in my mind should be enough to warrant humans protecting animals and ceasing experimentation on them. Have some human decency and jus

7:52PM PDT on May 19, 2013

sounds like these scientists are practicing satanists who enjoy torturing innocent animals. i hope they all rot in hell.

4:18AM PDT on Apr 26, 2013

STOP VIVISECTION donne la possibilité aux citoyens d'exprimer leur NON à l'expérimentation animale et d'exiger de l'Union européenne un parcours scientifique avancé, protégeant les droits des êtres humains et des animaux.

Check this link !it has links in many languages!
Lets end vivisection once for all!

12:02PM PDT on Apr 25, 2013

The EU is currently looking seriously on stopping the use of animals in research ,due to the lack of accuracy and ethics.more and more people are opposed to vivisections so keep fighting this atrocity ,petitions MPs et representative,put pressure so your taxes will goes into funding is very sad hat some people are spreading lies and myths they will tell BS so gross and ridiculous !,we all knows the horror animals are going through in the sadists 's hands.those people are sometimes paid by labs to troll and litter pages such as this to infuriate people with ethics and morals who are totally revolted by vivisection.dont let them bully you and keep on fighting for what is right and to protect innocent,voiceless animals ,STOP CRUEL REVOLTING USELESS VIVISECTION!!!!

1:01AM PDT on Apr 18, 2013

That is correct, Pamela, they cannot give consent.

I would gladly give consent to have an eye stitched closed and to spend a year in darkness if it would cure blindness for others. I would even give consent for my eyesight to be lost forever if it would cure blindness. That’s because I am a human: I am capable of understanding and empathising with the suffering of others, and have an inborn desire to ease that suffering as much as I can.

No animal has that understanding or desire. It has no plans for the future and no concept of death. It does, however, feel pain and stress, so animals in research are very carefully supervised and humanely treated. It is sad, and the researchers hate it, but if there can be no research testing on animals, there can be no further research, period. Nothing. No cure for anything, no improved treatments, no hope.

5:10AM PDT on Apr 17, 2013

5.49pm PDT - Lynda H " Scientists cannot experiment on young children: they are not able to understand and give consent."


11:42AM PDT on Apr 15, 2013

that's horrible! there is no excuse for that kind of treatment to an animal (kitten or otherwise).

1:04PM PDT on Apr 11, 2013

Sorry it seems the same post got posted numerous time wasn't attented and I can't delete!
Have a lovely day :)

12:55PM PDT on Apr 11, 2013

World Day for Animals in Laboratories is a UN recognised date to remember the millions of animals who suffer and die behind the walls of laboratories. Please join us in Oxford on 27th April and make your
voice heard for the millions of victims of vivisection, both human and animal.

For more information, including details of transport to the march and rally, visit the World Day for Animals in Laboratories website or contact us, see below

12:54PM PDT on Apr 11, 2013

World Day for Animals in Laboratories is a UN recognised date to remember the millions of animals who suffer and die behind the walls of laboratories. Please join us in Oxford on 27th April and make your
voice heard for the millions of victims of vivisection, both human and animal.

For more information, including details of transport to the march and rally, visit the World Day for Animals in Laboratories website or contact us, see below

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